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arXiv · 0804.2909

Thickness dependence of the exchange bias in epitaxial manganite bilayers

A. L. Kobrinskii·Maria Varela·S. J. Pennycook·A. M. Goldman
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Abstract

Exchange bias has been studied in a series of La2/3Ca1/3MnO3 / La1/3Ca2/3MnO3 bilayers grown on (001) SrTiO3 substrates by ozone-assisted molecular beam epitaxy. The high crystalline quality of the samples and interfaces has been verified using high-resolution X-ray diffractometry and Z-contrast scanning transmission electron microscopy with electron energy loss spectroscopy. The dependence of exchange bias on the thickness of the antiferromagnetic layer has been investigated. A critical value for the onset of the hysteresis loop shift has been determined. An antiferromagnetic anisotropy constant has been obtained by fitting the results to the generalized Meiklejohn-Bean model.

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A. L. Kobrinskii, Maria Varela, S. J. Pennycook, A. M. Goldman. 2008-09-18. Thickness dependence of the exchange bias in epitaxial manganite bilayers. https://doi.org/10.1103/physrevb.79.094405

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